Machine for electrocyanid chlorination process



4R. T. slLL. M ACHINE FOR ELECTROCYANID CHLORINATION PROCESS.'APPLICATION FILED APR. I6, 1919. 1,368,362, Patented Feb. 15, IILQZL"1l/.ill 1 v a. ...Ww/1| v PATENT OFFICE.

RUSH T. SILL, OF LOS ANGELES, CALFORNIA.

MACHINE FOR ELECTROCYANXD GELORTATION PROCESS.

Application filed April 16,

To all whom t may concern Be it known that l, RUSH T. Sinn, a' citieenof the United States, residing at Los angeles, in the county of LosAngeles, State of California, have invented new and useful lmprovementsin Machines for Electrocyanid Chlorination lrocesses, of which thetollowing is a specification.

rthis invention relates generally to that class of ore treatingmachinery in which` a pulp or pulverized value carrying material issubmitted to the action of a cyanid solution or' other dissolving agentin the presence of an electrical current. Such processes may be carriedout in a variety of manners; and l have developed a particular method orprocess for carrying out such an electrocyanid process in the presenceof chlorin liberatcd by the electrical action from sodium chlorid putinto the pulp. The present invention has for its general object theprevision of mechanism for the efficient carrying on of such processes.This machine is particularly effective in carrying on my electrocyanidchlorination process, but it will be readily understood that the machineinvention is not limited specifically to the chlorination process butmay be applied to such a. solvent process as is herein broadly referredto.

Due to several advantageous features and accomplishments of my improvedmachine, obtain results which are far superior to those obtained byother machines of which l am aware. Among the advantageous featureswhich l may preliminarily mention before going to a detailed descriptionof my machine are the following:

(1) The constant and steady circulation of liquid pulp between spacedelectrodes, in such a manner as to keep the positive elecA trode alwaysclean and in such a manner as to expose every particle of the pulp tothe inter-electrode action;

(2) Iteration ofthe pulp by means of an air-litt device which is apreferred method of causing pulp circulation. ln connection with thesemajor features of the machine, there are many other features, some ofthem more or less specific, which will be better understood from thefollowing detailed description of a preferred form of machine embodyingmy invention; reference for this purpose being;v had to the accompanyingdrawings, in which# Figure 1 is a. vertical central section ofSpeoca'tion of Letters Patent.

Fatented Feb. 15, 1921.

191i). Serial No. 299,375.

my improved machine; Fig, 2 is a bottom plan of the rotating electrode7said view being taken as indicated by line 2-2 on Fig. 1; Fig'. 3 is anenlarged detail section taken as indicated by line on Fig. 2; Fig. 4 isa detail section taken as indicated by line elllon Fig. 1; Fig. is anenlarged detail icction talren on line 5-5 of Fig. 1; and 6 is anenlarged detail section taken as indicated by line 6-6 on Fig. 1.

ln the drawings l show a circular tank preferably of wood with sides 10and bottom 11. @n the bottom 11 l place a metallic cathode plate 12 andimmediately above this cathode plate there is an anode plate 13preferably made of plate iron or other suitable metal and constructed inseveral sector-sections with flanges lil turned up at their edges.'lhese sector-sections are secured together by bolting their flangestogether; and the whole anode plate is secured to the lower end of ahollow column 15 by the expedient of bolting the lianges 11i on oppositesides of flanges 1G, which project from the lower end of the hollowcolumn. This hollow column 15 forms the upward central passage for theliquid pulpsfrom the inter-cleo trede space; and it also convenientlyforms the driving means whereby the upper electrode is rotated. 1t willbe understood however, that, so far as the 'function of the column as avertical passage is concerned, it is not necessary for it to rotate.This hollow column may be formed in any desired manner, as by casting itas an integral piece;

Aand its lower end may be flared as indicated at 1'? for the easy andsmooth passage of the "liquid pulp upwardly into it. Near its upper endthis hollow column has a plurality of discharge openings 18, shown hereas three in number. To strengthen the column at the openings, l provideflanges 19 between the openings, which extend downwardl from a circularflange 19 above the openings and connect below with a circular slopingapron 20 which directs the discharge outwardly instead of allowing it to.fall directly downwardly. it the discharge Opeliings 18 there is aninverted conical deflector 21 adapted to deiiect the upwardly iiowingstream of pulp outwardly to the outlets; and the flange 19a may assistin or continue such defiecting action.

Column 15 is suspended on a shaft 25 which may also be hollow, thisshaft running in bearing 26 and being suspended by an end thrust bearing2'?. The shaft is driven by a gear 28 driven in turn by gear 29 from apulley 30, or any other suitable driving means. Bearings 26 and 27 aresuspended on a suitable frame work 31 in a central position over thetop'of the tank. The frame work rests upon the edges of the tank, andthere it has adjusting screws' 32 by means of which the frame may beadjusted vertically in position, thereby adjusting the vertical positionoi' the electrode 13 with reference to the lowerl stationary electrode12. By this means the space between the electrodes may be accuratelyadjusted tosuit any particular circumstances and the rotating plate maythus be also accurately leveled with reference to the stationary plate.

In order to properly suspend the rotating plate on the hollow column andto keep it in true alinement, l provide brace rods 55 which extend outto the flange ont the plate. These brace rods may have turn-buckles 36so'that they may be accurately 'adjusted to accurately aline the plateso that it will truly rotate in the proper plane. l may ro vide asuitable number of paddles 37 mounted at their inner ends on the column15 and supported at their outer ends on the brace rods 35, these paddlesserving to keep the liquid pulpin .constant circulation above therotating plate so as to cause an outward movement of the liquid pulptoward the ou er edge ol the rotating plate. The outer edge of therotating plate is fairly close to the tank wall, allowing suiiicientspace around its entire periphery for the passage of the liquid pulparound and under the edge of the plate to enter the inter-electrodespace.

On the bottom ol' electrode 13 l provide a suitable number of membersIl() in the form of pump runners which are designed for the purpose ofcausing inward moveh ment of the pulp toward the central column. rlhesemembers 40 are made of insulating material (l make them of wood) and aresecured to plate 13 by bolts 40a vhose heads 41.0b are sunk into thewood and arecovered by a tightly fitted wooden plug 40C. ln a machine ofsubstantial size the rotating elec* trode rotates fairly slowly so as tonot lagitate the pulp. It is an object to keep the pulp flowing evenlyand constantly without over agitating it, or without any substantialagitation at all. Pump runners 40 are designed to suit the speed ofrotation and to give a smooth even inward flow o'll the pulp in theinter-electrode spa-ce. These pump runners of course aid in lifting theliquid through the central column; and they may be so designed as to doallot the lifting work. It the speed of rotation be somewhat increased.the runners can be designed to do more or all of the lifting work. Thus,in a machine of 2O foot diameter, or so, at 3--5 revolutions perminute,` the runners do a substantial part of the lifting. lf the speedbe increased to, say, 15 revolutions per minute, the runner-scan be sodesigned as to do all the lifting work, at Vthe same time handling thepulp smoothly and without agitation. vllowevr-ir, l prefer to designthese pump runners so that they will only assist in the lifting work andwill, by the nature of their action, keep the pulp flowing smoothly andevenly in all parts of the inter-electrode space, while the-major partof the iii-ting work is done by the airliit which also aerates the pulp.lt will be readily seen that the pump runners not only positively helpthe lift but also perform a i'unction of regulation to regulate and makesmooth and even the iiow of pulp through the inter-electrode space;keeping the pulp flou equally in all parts of the inter-electrodespaces, so as lto subject equally all parte oi the thin flowing streamtothe electric action.

New, although l may use any desired form of lifting' means for vtheliquid pulp in the column, l prefer to use an airlift means because thatmeans aerates the pulp at the same time that it lifts it.l For thispurpose l provide a conical air nozzle 50 having in its upper part airopenings 51 adapted to deliver air in line streams into the liquid pulp.

These openings are so'directed that their jets of air tend to overcomeor neutralize the rotary motion et the pulp in the column, thusovercoming any tendency of the solid particles to be thrown lto theoutside of the column and more or less cling` to its wall. The conicalshape of the nozzle allows room for the expansion of the mixed fluids asthe air is fed into the pulp. The nature of an airlii't being wellunderstood, it is not necessary here to explain it in detail. l utilizeair pressure or live pounds per square inch or so, delivered through theair pipe 52 under control of valve 53. Pipe 54, which is controlled byvalve 55, is a pipe for draining or for introducing cleaning water orother iluid to the nozzle to clean the appa" ratus. The air nozzle isinsulated, asat 56, from the surrounding` cathode plate, and is alsoinsulated from the anode plate by being spaced therefrom, so that thereis no tendency :'or the current to short-circuit through the air nozzle.

The tank may have one or more valve controlled outlets at 60 which maydischarge into a suitable trough as illustrated at 61; The process maybe carried on continuously by continuous operation oi the machine andcontinuous introduction and withdrawal of pulp; crit may be operated onthe batch rinciple by introducing a batchof pulp and treating it todeposit the valves on the deposit plate 12 and then withdrawing thespent pulp and introducing a new charge.

Such methods of operation are readily understood in the art and need nospecific description.

The cathode deposit plate l2 is preferably an amalgamated copper plate.llllectrical connections are made to this cathode plate by any suitableelectrical connector and to the anode plate by an electrical connectionwhich may be made, as diagrammatically illustrated at 62, to the upperend ot the hollow column or shaft 25. L direct current of comparativelylow voltage and ot low amperage per square loot ot surface, is used. lna machine oi say 2O it. diameter, the circulation of liquid pulp may beat any eiiicient rate; and without limiting ourselves to any particularrate oi iiow, we may state that, about 1500 gals. per minute more, orless, has given effective results. This circulation is fast enough tokeep the solid particles in suspension; and furthermore any tendency ofthe solid particles to settle is caused by the action ci detlector 2Oand paddles 37 to be at the outer edge of the rotating plate rather thanat its inner part; and the settlement, if any, being at the outer edge,these particles are of course drawn directly into the stream which isconstantly passing around and under the edge of the anode plate. Thiswhole circulation oi liquid passes through the relatively thin spacebetween the two plates, in a smooth evenly iiowing stream. lIhus thereis Va relatively thin sheet oi liquid pulp being constantly subjected tothe electrical action, and to the chemical reactions induced by theelectrical action on. the solvent and on the other substances which maybe intro duced. The action of the pump runners in keeping the liquidmoving at all times, also olf course keeps the solid mattei' moving andkeeps it in suspension and therefore keeps the deposit plate l2 clean atall times. The valves deposited on the cathode deposit plate maybeperiodically cleaned olf; the upper structure 3l and the rotatingparts being liitedout of the tank `for this purpose.

rlhis apparatus has proved to be exceptionally efficient inclectro-cyanid work and particularly in carrying on the process oielcctro-cyanid chlorination; being highly effective both on clean oreand on ores containing organic impurities. The cyanid or otherdissolving agent may be added tothe pulp liquid either before or afterplacement in the tank; as may also the salt which is introduced forconductivity and to give the chlorination action. The dissolution anddeposit of precious metals takes place in this machine in a time periodof one-eighth to onc-twentieth of that required for the ordinary cyanidprocess; with complete or very nearly complete precipitation of preciousmetals from the solution, which may then be regenerated to be usedagain.. Furthermore, a smaller quantity ci cyanid is used in thismachine than in other machines or processes.

ik very marked advantage in my machine is in this: that its capacity canbe very easily increased by simply increasing the depth ot pulp,increasing the depth of the tank if necessary. This 4can be done becaise the method oi operation can be carried on eiiiciently regardless oi'the depth of pulp. My machine is not limited at all to a shallow body ofpulp. Another distinctive Vfeature, and one which is i'urther emphasizedby the possibility ci operation oi a great depth of pulp, is this: thatl move the large mass ci pulp-all that above the upper plate-with ratherthan against centrifugal actiong only the smaller part in the thin spacebetween the plates being moved inwardly.

llVhile l have proceeded to a description which is full in particular'and detail, l have done so tor the purpose of rendering my inventionclearly and fully intelligible to those skilled in the art and not forthe purpose of limiting my invention to the particular and specificthings herein set forth; believing my invention to be broad in itsnature andV scope and not limited except as is herein after specificallyset forth in the following claims, which claims are to beread and interpreted broadly as applying to the inven tion herein typified, as wellas specifically as applying to the particular things herein set forth.

llavingdescribed a preferred iorm ot my invention, l claim:

l. ln combination, a, tank, an electrode plate in the tank, anotherelectrode :plate in the tank spaced above the iirst mentioncf plate, ahollow column leading upward 'from the central part ci theinter-electrode space and discharging above the upper electrode, andmeans 'for raising liquid pulp through the column.

2. ln combination, a tank, an electrode plate in the tank, anotherelectrode plate spaced a relatively small distance from the iirstmentioned plate; the capacity ot the tank relatively to the capacity oitthe interelectrode space being comparatively A i.; and means to causerotation and outuard centrifugally assisted iiow ci the liquid in thetank exterior ot the inter-electrode space, and to cause inward iiow ciliquid in said inter-electrode space.

3. In combination, a tank, an electrode plate in the tank, anotherelectrode plate spaced a relatively small distance from the firstmentioned plate; the capacity ot the tank relatively to the capacity cithe interelcctrode space being comparatively large", and means to causerotationand outward centrifugally assisted flow ot the liquidin the tankexterior ot the inter-cl trede ice tank.

V4. In combination, a tank, an electrode plate inthe tank, anotherelectrode plate in the'tankv spaced above the first mentioned' plate, ahollow column leading upwardly from the central part of theinter-electrode space and discharging above the upper electrode, andmeans for raising liquid pulp through the column, the upper plateextending out toward the wall ot the tank and being imperforate so thatthe liquid pulp must travel outwardly over the upper plate and aroundits edge in order to reach the space between the plates.

5. In combination, aV tank, an electrode plate in the tank, Vanotherelectrode plate in the tank spaced above the first mentioned plate, a`hollow column leading upwardly from. the central part of theinter-electrode space and discharging centrally above the upperelectrode, means for raising liquid pulp through the column to bedischarged into the tankat its upper end, and means forL directing thedischarge from the lcolumn outwardly so as to cause anfoutward movementofliquid pulp over the upper plate toward itsedge.

' 6. In combination, a tank, an electrode plate in the tank, anotherelectrode plate in the tank spaced above the first mentioned plate, ahollow column leading upwardly from the central part of theinter-electrode space and discharging centrally above the upperelectrode, means for raising liquid pulp through the column to bedischarged into the tank at its upper end, and means for causing outwardmovement of the liquid pulp above the upper plate.

7. In combination, a tank, a lower electrode plate therein, an upperelectrode plate spaced above the lower plate and rotatable about asubstantially vertical axis, a hollow column leading upwardly from theinterelectrode space and discharging above the upper electrode, meansfor raising` liquid pulp through the hollow column, and means on theunder side ofthe rotating plate acting to move the liquid pulp inwardlytoi ward the center in the inter-electrode space.

8. In combination, a tank, a lower elec trode plate therein, an upperelectrode plate spaced above the lower plate and rotatable about asubstantially vertical axis, a hollow column leading upwardly from theinterelectrode space, and means to create an inward flow of liquid pulpin the inter-electrode space and to raise the liquid pulp through thehollow column.

`9. In combination, a tank, a lowerfelectrode plate therein, van upperelectrodeplate spaced above `the lower plate and rotatable anodesupported atfa suitable distance from Y the deposit plate, a hollowcentral column, and means fon -moving a liquid pulp through the hollowcentral column.

l1. In combination, a tank, a cathode deposit plate at the bottom of thetank, a rotating metallic anode supported at a suitable distance abovethe deposit plate, a hollow central column, and means :tor moving aliquid pulp upwardly through the hollow central column. p

12. In combination, a tank, a cathode deposit plate at the bottom of thetank, a rotating metallic anode supported at a suitable distance abovethe deposit plate, a hollow central column, means Vfor moving a liquidpulp upwardly through the hollow central column, and a series ofnon-conducting fluid controlling means mounted on the under side of therotating anode to regulate the movement of the liquid pulp inwardlyunder 'the anode to the hollow central column.

13. In combination, a tank, a cathode deposit plate at the bottom of thetank, a rotating metallic anode supported at a suitable distance abovethe deposit plate, a hollow central column, and means for moving aliquid pulp upwardly through the hollow central column, said lastmentioned means comprising means for forcing a fluid under pressure intothe hollow central column to produce an upward circulation of the fluidpulp, the hollow central column having an outlet at its top throughwhich the iiuid discharges into the tank, thus creating a circulation ofthe liquid pulp which moves outward and downward to the outer edge ofthe rotating anode, and then moves inwardly under the rotating anode andover the cathode deposit plate, and then moves upward through the hollowcentral column in a closed circuit of circulation.

14;. In combination, a tank, a cathode deposit plate at the bottom ofthe tank, a rotating anode plate supported above the deposit plate androtatable about a substantially vertical axis, a hollow central columncommunicating below withV the inter-electrode space and dischargingabove the upper rotating electrode, air vliift means for raising liquidpulp in the column, means for causing movement of liquid pulpabove theupper electrode outwardly toward the peripher of vthe upper electrode,said electrode eing limperforate'so that the liquid pulp must llow toits edge in order to enter the inter-electrode space, and means on theunder side of the rotating electrode to move the liquid pulp inwardlytoward the column.

l5. ln combination, a tank, a cathode deposit plate at the bottom ci'the tank, a rotating anode plate supported above the deposit plate androtatable about a substantially vertical axis, a hollow central columncommunicating below with the inter-elec trode space and dischargingabove the upper rotating electrode, air litt means for raising liquidpulp in the column, means above the rotating electrode and rotatingtherewith and adapted to throw the liquid pulp outwardly toward theperiphery of the upper rotating electrode, said electrode beingimporter-ate so that the liquid pulp must flow to its edge in order toenter the inter-electrode space, and pumping means on the under side otsaid electrode to cause inward movement oit the liquid pulp toward thecentral column.

16. ln combination, a tank, cathode deposit plate at the bottom oli thetank, a rotating anode plate supported above the deposit plate androtatable about a substantially vertical axis, a hollow central columncommunieating below with the inter-electrode space and discharging abovethe upper rotating electrode, air lift means for raising liquid pulp inthe column, means above the rotating electrode and rotating therewithand adapted to throw the liquid pulp outwardly toward the periphery ofthe upper rotating electrode, said electrode being imperforate so thatthe liquid pulp must flow to its edge in order to enter theinterelectrode space, and pump runners of a nonconducting materialmounted on and projecting below the lower suriace oit the rotan ingelectrode and adapted by rotation to move the liquid pulp inwardlytoward the central column.

17. In combination, a tank, an electric deposit plate at the bottom oi'the tank, a rotating electrode plate supported at a suitable distanceabove the deposit plate, a hol low ycentral column, and means tor movinga liquid pulp upwardly through the hollow central column, the hollowcolumn hai/'ing discharge openings at its upper end, and a circulardeflector around the hollow column immediately below the openings todirect the liquid outwardly.

18. ln combination, a tank, an electrode deposit plate at the bottom oitthe tank, a rotating` electrode plate supported at a suitable distanceabove the deposit plate, a hollow central column, and means for moving aliquid pulp upwardly through the hollow central column, the hollowcolumn having discharge openings at its upper end, and defiector meansinside and outside the hollow column at the discharge openings todeflect the upward stream of liquid and direct it outwardly horizontallyinto the tank to cause outward movement of the liquid pulp above theupper rotatingelectrode.

19. ln combination, a suitable tank, a cathode deposit plate on thebottom `of the tank,- a rotating element in the tank above the cathodedeposit plate, said rotating element embodying a horizontal anode platewith its edges close to the side of the tank and allowing a passage-wayaround the edges of the anode plate and between the anode plate and thecathodey plate, and a central hollow column carrying the anode plate andopen at its lower end to the lspace under the anode plate and havingdischarge openings at its upper end; and means to cause upward movementof a liquid pulp in the hollow column.

20. ln combination, a suitable tank, a cathode deposit plate on thebottom of the tank, a rotating element in the tank above the cathodedeposit plate, said rotating element embodying a horizontal anode platewith its edges close to the sides of the tank and allowing a passagewayaround the edges of the anode plate and between the anode plate and thecathode plate, a central hollow column carrying the anode plate and openat its lower end to the space under the anode plate and having dischargeopenings at its upper end; and means to cause upward movement of aliquid pulp in the hollow column; said rotating element being suspendedfrom and rotatable in an over head bearing adjustably supported on thetank.

2l. ln combination with a tank, an elec trede on its bottom, a rotatingelectrode above, and means for adjust-ably and rotat ably carrying' saidrotating electrode embodying a shaft member on which the electrode issuspended, an upper bearing for the sha-itt, and a trame carrying thebearing and spanning the top of the tank and adjustably mounted withreference to the tank so that the position of the suspended electrodemay be adjusted.

Q2. ln combination, a tank, an electrode deposit plate' at the bottom ofthe tank, a rotating electrode plate supported at a suitable distanceabove the deposit plate, a hollow central column, and means for moving aliquid pulp upwardly through the hollow central column, said meansembodying means 'for counteracting within the column the rotation andcentrifugal action oi the pulp due to rotation of the anode.

23. ln combination, a tank, an electrode deposit plate at the bottom ofthe tank, a rotating electrode plate supported at a suitable distanceabove the deposit plate, a hollow central column, andineans for moving aliquid pulp upwardly through the hollow central column, said meansembodying air jets directing air into the pulp in the col- .i umn indirections opposite to the rotation of the anode.

24. In combination, la tank, an electrode deposit plate at the bottom ofthe tank, aV

rotating electrode plate supported at a suitable distance above thedeposit plate, ahollow central column, and means for moving a liquidpulp upwardly through the hollow central column, said means embodying anupwardly tapering air nozzle in the column.

25. In combination, a tank, a plate in the tankl spaced above the bottomof the tank,

a hollow column leading upwardly froml said means including means toaerate the liquid.

between the space below'the plate, and the spacerabove the plate, andlmeans on the plate and adapted by virtue of its rotation to causeinward movement of liquid beneath the plate toward its center.

28. In combination, a tank, a rotatable plate in the tank spaced abovethe bottom of the tank, there being an opening at the center of theplate forming communications between the space below the plate and thespace above the plate, and means on the plate and adapted by virtue ofits rotation to cause inward movement of liquid beneath the plate towardits center, said means embodying curved runners adapted to cause inwardlow of the fluid.

In witness that I claim the foregoing I have hereunto subscribed my namethis 8th day of April, 1919.

RUSH T. SILL.

Witness VIRGINIA BERINGER.

